No power steering on a Terramite

[cstamm81]

I am digging into an issue with a new to me Terramite T5C. It has power steering via a 2 way hydraulic cylinder. The steering column goes directly into a steering box, with 4 hydraulic lines coming off of it. 2 go to the steering cylinder, 2 go to the hydraulic pump.
It feels like I have no power steering. I disconnected the cylinder from the front end, so that I could see if the cylinder would cycle. Well it does cycle in and out, but it cycles with a lot of effort turning the wheel, same as when it was connected. So, I must have some hydraulic fluid getting to each side of the cylinder or it would not cycle at all. Do cylinders themselves sometimes get very tight? It seems like there is not enough flow, but I am not sure how to check that. And I would also think I would have full flow in one direction if it was a partially blocked or kinked line.
I do not understand how the input from the steering wheel signals a valve to send fluid to the one side of the cylinder. Anyone have any suggestions?

 

[wdchyd]

if the steering wheel turns and turns with no pressure build up at the end of stroke, then the seals in the cyl may be worn and by-passing (time to repack)

if the steering seems hard to steer then the hyd pump pressure/flow may be low (test with hyd guage)

if you have the cyl off make sure the hyd rod is not bent (turn it by hand)

if all these check out then the steering valve may be worn or broken internally (usually time for a new steering valve)

 

[the old grind]

There could be something amiss in the steering box. Depending on year/model T5C you may have the older steering setup that even TerraQuip can't do everything for (offset column), tho' they will do their best. I'd shut 'er down, disconnect one line from the cylinder, and get something to catch the spills. After working some oil & bubbles out it should move freely by hand tho' with some stiffness. Too easy can mean piston/seal failure. It may need to be rebuilt, and with most places there'd be a minimum $$ to have it looked at. If it really seems ok the phone will get you where the internet won't.

Have your Ser # handy if you T-M call for help. (They've been awesome every time I did!) If you have a center column, all the better for you. Good luck, & let us know ....

 

[cstamm81]

on the hyd gauge idea, is the gauge installed in line between the line and cylinder? Or does it dead head the line and take the reading that way?

 

[cstamm81]

I actually now have two T5C's, one with a hoe and this one with a factory 3 point hitch. This machine is early 2000's and it has the steering wheel offset, as does my other one. If I turn the wheel to the right with any kind of speed with the machine off it makes a clicking noise from the steering box I believe. What do you mean by "Terraquip can't even do anything for the offset columns"?

I will try out the idea of cycling the cylinder by hand with a line off. I'm fine with having to replace parts, just want to make sure I'm replacing the right ones!

 

[J_J]

cstamm81 ,

You would put the gage after the steering pump or the source for the steering fluid. Then anything that causes pressure will be reflected on the gage.

 

[cstamm81]

is the gauge tee'ed in? As in a tee fitting on the source line for the steering cylinder? Also, what would a typical range of pressure be? The machine develops 2400 PSI and 7 GPM, but I am assuming that full flow goes to the backhoe and there would be less pressure at the power steering circuit...

 

[J_J]

Most steering circuit pressures are around 1000 to 1500 psi.

If you tee it into the input hose for the steering valve , it will indicate what pressure the cyl is developing.

 

[cstamm81]

That's great thanks. I will pick up a 1/4" NPT tee and a hydraulic gauge, and see where I am at. I'm hoping it's the cylinder (never knew one to get tight like this, just leak) or a blocked / kinked hose. It feeds from the hydrostatic pump, and if the issue is in there I am in trouble.

 

[the old grind]

cstamm81, that was me saying "... can't do everything for". Here's what I was told a few yrs ago: The 'obsolete' steering box hasn't been made or supported for years. There was no source of replacements or parts available even to them at the time. They were able to supply a face (thrust) seal to resolve a leak. I was cautioned by the svc mgr against disassembling the old-style (offset) steering box to replace the seal without experience or somehow-unavailable technical info/manual as being a nightmare of parts flying. I spoke to another guy who insisted that I ring him back when I was ready to be guided step by step and safely do the least necessary to change the seal. btw: For this I spoke well of TerraQuip's service a time or two ...

The seal is an odd size not easily found at the supply houses in the size required (~ a US Quarter), tho' I'll continue to search for another source if wear might shorten its life. Here's the bit that'll get a few nod's of acknowledgement. The parts was $62, shipped in a 9x12 bubble envelope, and for another $14 Fed-Ex dropped that into the US mail for them. (well-deserved F-E bashing forgiven, as always)

I was assured that 'upgrading' to the newer style column wasn't possible. (??) I doubt I'd want to pay their rates for one for sure, but at this point I'm beginning to wonder if I'm considered to have two left feet & ten thumbs, and getting over-cautioned advice. T-Ms are enough like giant lawn tractors that there's room to tinker under the dash. After having R&R'd the guts & gears of a DeWalt 18v hammer drill not much would scare me. I might be in that box with the new seal already, but .. (don't laugh, ok?...) I'm still pickling the steering wheel's hub in Kroil to get the !%$@ thing off the shaft in one piece without setting up an electrolysis rig to de-rust it. :-/

Mebbe I went to far too soon with the steering drama, but believe me .. if it's all that much, I'd love to be the guy that figures out & shares for those of us with T5Cs' older steering boxes.

 

[wdchyd]

cstamm81, that was me saying "... can't do everything for". Here's what I was told a few yrs ago: The 'obsolete' steering box hasn't been made or supported for years. There was no source of replacements or parts available even to them at the time. They were able to supply a face (thrust) seal to resolve a leak. I was cautioned by the svc mgr against disassembling the old-style (offset) steering box to replace the seal without experience or somehow-unavailable technical info/manual as being a nightmare of parts flying. I spoke to another guy who insisted that I ring him back when I was ready to be guided step by step and safely do the least necessary to change the seal. btw: For this I spoke well of TerraQuip's service a time or two ...

The seal is an odd size not easily found at the supply houses in the size required (~ a US Quarter), tho' I'll continue to search for another source if wear might shorten its life. Here's the bit that'll get a few nod's of acknowledgement. The parts was $62, shipped in a 9x12 bubble envelope, and for another $14 Fed-Ex dropped that into the US mail for them. (well-deserved F-E bashing forgiven, as always)

I was assured that 'upgrading' to the newer style column wasn't possible. (??) I doubt I'd want to pay their rates for one for sure, but at this point I'm beginning to wonder if I'm considered to have two left feet & ten thumbs, and getting over-cautioned advice. T-Ms are enough like giant lawn tractors that there's room to tinker under the dash. After having R&R'd the guts & gears of a DeWalt 18v hammer drill not much would scare me. I might be in that box with the new seal already, but .. (don't laugh, ok?...) I'm still pickling the steering wheel's hub in Kroil to get the !%$@ thing off the shaft in one piece without setting up an electrolysis rig to de-rust it. :-/

Mebbe I went to far too soon with the steering drama, but believe me .. if it's all that much, I'd love to be the guy that figures out & shares for those of us with T5Cs' older steering boxes.

Maybe I haven't read all the facts yet, but what you describe is a steering valve......with these steering valves you need to use OEM kits to reseal them, yes the parts are not common generic parts, but are repairable if you have the right seal kit

Another factor is if you need parts other than a seal kit (shaft, geroler, valve plates) then fugitaboutit, buy a new unit, the same displacement and matching steering collumn/wheel

As far as being obsolete I'd say that maybe the case for the dealer but seal kits are available at hydraulic shops and are not obsolete for them with the right model code tag

Beware resealing one of these is not for the faint of heart, it requires expertise to retime the internal gears and valve plates for a successfull repair and a bench test to check integrity of the repair

Another thing, if the steering unit is found to be faulty after troubleshooting, then replace it......a seal kit will not fix a mechanical problem internally.....these are very fussy units

Do you guys have pix of the steering units on these Terramites??

 

[J_J]

Looking at the T5D, and the T5C may be the same, the hydrostatic pump feeds the steering valve.

About 3/4 down in the PDF Illustration 4.42

http://ww3.grandrental.com/Portals/109/PDF/Terramite Instruction Manual.pdf

 

[the old grind]

Wcdhyd, "thank you for your support". My leak is apparently from accum moisture freezing inside the mast jacket and pushin'/pullin' something out of whack (No wheel center button, but deflector now in place). T-M's techs said only the input shaft's 'face seal' was damaged (internal, for sure) if it still works ok despite dribbling out & onto my britches-leg. Can I look to you for more when I get the $&!@ wheel off and the column/box out?

JJ, I wish the pieces were just as similar as the schematics imply. My manual show an entirely different box with the T5C offset column. Apparently it's not a model diff as a 'year' thing. Thanks!:thumbsup:

Pics will be here when I get something going. btw: Whaddya got to soften rust when a prolonged and protected Kroil-soaking isn't working??? My puller's gouging some poly without budging up off that rusty &$%# stg-wheel spline. Electrolysis would require a mat-soak vs a dip while still on the tractor, and that sounds like a lotta fuss. Only thing else I can think of is phosphoric acid, if it cuts thru the Kroil easy enough. Other ideas??...

cstamm81', my manual shows an exploded view of the box on P 2.16. (I'll put it up when I can get to their site.) I see the bolts holding the jacket onto the pump are also what holds the body 'stacks' together and are the first thing to get apart. I'll chance going in SAP but hopefully you won't have to if we can get your test setup right & be sure what you've got. I'd swap a hose out if you suspect pressure has leaked between its wire mesh and inner lining. btw: It might not relax much when pressure's released, so it could be easy to spot (?)...

 

[ptgdigger]

Heres a few pics that contain a troubleshooting chart for a very similar machine with the same steering setup.

Ray

 

[ptgdigger]

Don't know what happened to the second image that sized it different they were all from the same file, but anyway the problem you are describing is the first one in the first image. You should either have a priority flow divided pump or a separate priority divider at the pump output, the purpose of this is to make certain that you always have flow for steering no matter what else you are using. That would be the first thing to test to make sure there is flow to the steering circuit, for a single small steering cylinder it is going to be in the 2-4 gal per minute range, I don't know the spec on Terramite steering valves though so i can't give you a rock solid number. It gets more complicated if they used load sensing, then we're really gonna need help from WDCHYD


Ray

 

[wdchyd]

Don't know what happened to the second image that sized it different they were all from the same file, but anyway the problem you are describing is the first one in the first image. You should either have a priority flow divided pump or a separate priority divider at the pump output, the purpose of this is to make certain that you always have flow for steering no matter what else you are using. That would be the first thing to test to make sure there is flow to the steering circuit, for a single small steering cylinder it is going to be in the 2-4 gal per minute range, I don't know the spec on Terramite steering valves though so i can't give you a rock solid number. It gets more complicated if they used load sensing, then we're really gonna need help from WDCHYD


Ray

Yes, true......if you don't have flow (with pressure) then nothing downsteam will work right .......the flow/load meter would come in handy here

 

[wdchyd]

Nice chart Ptgdigger.....:thumbsup:

 

[ptgdigger]

Yes, true......if you don't have flow (with pressure) then nothing downsteam will work right .......the flow/load meter would come in handy here

Sure would, I've been coveting one ever since the other thread you talked about it :drool:

 

[ptgdigger]

Bad news , your symptoms seem like a no flow (or very low flow) issue, turns out rather than a priority gear pump or priority divider terramite uses an adapter plate in the trans to supply steering flow. So i'm betting that your troubleshooting will lead you to the transmission. You may be able to divert some flow from the auxiliary hydraulic system to have power steering but you will have to verify the working pressure of the steering system vs. the working pressure of the aux. system. If they are compatible then the only issue would be a chance that the steering would get erratic when using the loader while driving.



Ray

 

[cstamm81]

ptgdigger you are correct in that this is how the Terramite system works, based upon the drawings and other threads. Will I get any useful information by teeing in a pressure gauge before the steering cylinder just to see where I am at?